1. If you properly deploy the DXA Web App (incl. CD artifacts such as license file) on your local machine, all the functionality will work.
 2. See point 1. Everything should work, also if you are debugging.
 3. DXA Link Resolving just builds on CD Link Resolving. I'm not sure if you can suppress port 80 (would indeed makes sense). How does your `cd_link_config.xml` look?